Aseptic aerosol misting device

ABSTRACT

A handheld misting device has a housing having a dispensing window is arranged and configured to contain a sonic generator, a power source coupled to the sonic generator, at least one reservoir containing a liquid, and a conduit extending from the at least one reservoir to a nozzle removably coupled to the sonic generator. The sonic generator includes a converter and an elongate horn having a proximal end coupled to the converter and a distal end, and the nozzle is removably coupled to the distal end of the horn. Thus, the device delivers the liquid through a delivery opening formed in the nozzle, and activating the sonic generator energizes the liquid in the nozzle to generate an aerosol plume that is delivered through the dispensing window.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. provisional application62/248,682, filed Oct. 30, 2015, the complete disclosure of which ishereby incorporated herein by reference for all purposes.

FIELD OF THE INVENTION

The present invention relates to an aseptic misting device employing apermanent sonic generator and a replaceable liquid reservoir and nozzle.

BACKGROUND OF THE INVENTION

Spray and/or misting devices are often used to delivery cosmetic andgeneral health care liquids. Low cost systems employ droppers and/orsqueeze bottles with some form of nozzle through which the liquid isforced to provide a relatively uncontrolled dosage and droplet size.

Expensive systems may employ metering pumps and/or expensive aerosolforming components. For example, Hseih et al. U.S. Pat. No. 7,992,800and Hseih et al. US Pub. Pat. Appn. No. 20120318260 disclose nebulizersdriven by piezo-electric and/or magnetic drives to generate an aerosolmist.

Other examples include The Technology Partnership PLC, EP615470B1;Hailes et al., U.S. Pat. No. 7,550,897, and Brown et al. U.S. Pat. No.7,976,135, which disclose liquid projection apparatus employingtransducers to project liquid droplets from an outer face of a nozzle.

Finally, Terada et al. U.S. Pat. No. 6,863,224, Yamamoto et al. U.S.Pat. No. 6,901,926, and Esaki et al. U.S. Pat. No. 8,286,629 discloseultrasonic liquid atomizing devices.

Unfortunately, these expensive components can be contaminated throughrepeated uses and require careful cleaning or disposal.

What is needed is a relatively low cost system for delivering controlleddoses and particle/droplet size aerosol mists.

SUMMARY OF THE INVENTION

Surprisingly, we have found that ultrasonically atomizing a liquidthrough submillimeter-sized nozzles attached to the end of an elongatesonic horn provides inexpensive aseptic atomization by preventing theliquid contained in the reservoir from touching the ultrasonic horn.

In one embodiment, a handheld misting device has a housing having adispensing window is arranged and configured to contain a sonicgenerator, a power source coupled to the sonic generator, at least onereservoir containing a liquid, and a conduit extending from the at leastone reservoir to a nozzle removably coupled to the sonic generator. Thesonic generator includes a converter and an elongate horn having aproximal end coupled to the converter and a distal end, and the nozzleis removably coupled to the distal end of the horn. Thus, the devicedelivers the liquid through a delivery opening formed in the nozzle, andactivating the sonic generator energizes the liquid in the nozzle togenerate an aerosol plume that is delivered through the dispensingwindow.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a handheld aseptic misting deviceaccording to one embodiment of the invention.

FIG. 2 is a side view of the handheld aseptic misting device of FIG. 1with the housing removed to show the interior components.

FIG. 3 is a side view of the disposable cartridge of the handheldaseptic misting device of FIGS. 1 and 2 with the housing removed to showthe interior components.

FIGS. 4A-C are perspective views of various nozzle and receptaclecombinations useful in the handheld aseptic misting device of FIG. 1.

FIG. 5 is a detailed side view of the distal end of the sonic hornhaving surface features to prevent undesired misting of liquids that maymigrate to the distal end of the horn.

FIG. 6 is a perspective view of elements of a handheld aseptic mistingdevice according to a second embodiment of the invention

FIG. 7 is a schematic cross-section of a handheld aseptic misting deviceaccording to a third embodiment of the invention.

FIG. 8 is a schematic cross-section of a handheld aseptic misting deviceaccording to a fourth embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a handheld sonic misting device that ismore economical than conventional sonic misting devices, because therelatively expensive sonic generator and horn are isolated from liquidsdispensed by the misting device. Thus, the misting device can bereplenished with liquids without significant build-up of liquids on thehorn.

In one form of the device, a conduit delivers the liquid to be dispensedto the tip of the horn in a system arranged and configured to direct theliquid away from the horn, such that the horn is not contaminated by theliquid and further, subsequent liquids dispensed from the device are notcontaminated by previously dispensed liquids.

As shown in FIGS. 1-5, the handheld misting device 100 (including asonic generator 200, a liquid delivery system 300, and an electric powerand control system 400) useful to form an aerosol comprising liquiddroplets (referred to herein as a “mist” or “plume”) is contained withina housing 500. The sonic generator 200 includes a converter 202 and anelongate horn 204 having a proximal end 206 coupled to the converter 202and a distal end 208, opposite thereof, visible through an opendispensing window 502 in the housing 500. The converter 202 is coupledto the electric power and control system 400 through electricalconnections, such as wires (not shown).

The liquid delivery system 300 includes a collapsible reservoir 302, aconduit 304, a nozzle 306 having at least one delivery opening 308, anda linear motor 310. The piston 312 of the linear motor 310 contacts thelower surface 314 of the reservoir 302 to force liquid out of reservoirand into conduit 304. The linear motor 310 is also coupled to theelectric power and control system 400 through appropriate electricalconnections, such as wires (not shown). The conduit 304 conducts liquidfrom the collapsible reservoir 302 to the nozzle 306, and the nozzle 306is physically coupled to the distal end 208 of the elongate horn 204.The nozzle 306 is arranged and configured to dispense liquid from thecollapsible reservoir 302 to the atmosphere through the dispensingwindow 502 in the housing 500. The nozzle 306 is protected duringstorage by closing the dispensing window 502 with a cover 504.

Although the liquid delivery system 300 described above includes acollapsible reservoir 302 and a linear motor 310, one of ordinary skillin the art will recognize that other systems may be used. Thecollapsible reservoir and linear motor provide one solution to theproblem of delivering controlled volumes of liquid from the reservoir.Alternative systems may also be used. For example, the samefunctionality as the reservoir and pump may be delivered via one or moreof the following: pipette, syringe, squeezable bag, pressure actuatedreservoir, and even gravity feed.

In order to reduce the cost of operation of the handheld misting device100 of FIGS. 1-5, the housing 500 includes a first, electromechanicalsection 506 (shown in FIG. 2) that houses components including the sonicgenerator 200, the electric power and control system 400, and the linearmotor 310 of the liquid delivery system 300, and a second, liquidsection 508 (shown in FIG. 3) that houses the collapsible reservoir 302,conduit 304, and nozzle 306 having at least one delivery opening (shownas 308 a, 308 b, 308 c in FIGS. 4A-4C). As shown in FIG. 3, the liquidsection 508 is a separate, removable section that can be securelyattached to the electromechanical section 506. Alternatively, the liquidsection 508 may be an openable compartment in the housing 500 that isarranged and configured to receive replacement collapsible reservoir302, conduit 304, and nozzle 306.

The electric power and control system 400 includes a power source, suchas a rechargeable battery 402, that is electrically connected to anelectrical charging port 404 disposed in the housing 500. The electricpower and control system 400 also includes an on/off switch 406 and anactivation switch 408, both disposed on the housing 500, and one or morecontrol boards 410. The power source is preferably replaceable and/orrechargeable and may include devices such as a capacitor or, morepreferably, a battery. In a presently preferred embodiment, the powersource 402 is a rechargeable battery including, without limitation,lithium-based cells, including lithium polymer batteries. One example ofan internal power source is a lithium polymer cell providing a voltageof about 3.7 V that has a capacity of at least about 200 milliamp hours(mAh).

The interaction between the nozzle (shown as 306 a, 306 b, 306 c inFIGS. 4A-4C) and the distal end 208 of the elongate horn 204 is showngreater detail in FIGS. 4A-4C. The nozzle 306 is securely fitted into areceptacle 210 formed in the distal end 208 of the elongate horn 204.This substantial physical coupling permits the nozzle 306 to vibratewith the distal end 208 of the elongate horn 204 to trigger standingwaves that are the provide the ultrasonically driven mist dispensed fromthe nozzle 306. In preferred embodiments shown in FIGS. 4A-4C, thenozzle 306 extends away from the distal end 208 of the elongate horn 204to reduce the likelihood of the liquid leaking onto and contaminatingthe distal end.

In FIG. 4A, the nozzle 306 a is substantially cylindrical, comprises aplurality of delivery openings 308 a, and fits into a receptacle 210 aat the distal end 208 a of the elongate horn 204.

In FIG. 4B, the nozzle 306 b has a frusto-conical shape, comprises asingle, elongate delivery opening 308 b, and fits into a receptacle 210b at the distal end 208 b of the elongate horn 204.

In FIG. 4C, the nozzle 306 c has a trapezoidal cross-section, comprisesa substantially rectangular delivery opening 308 c, and fits into areceptacle 210 c at the distal end 208 c of the elongate horn 204.

The size, shape, number, and arrangement of delivery opening(s) 308 inthe nozzle 306 define the plume of mist generated by the misting device100. The delivery opening(s) 308 are dimensioned to delivery an aerosolmist. Preferably, each delivery opening has a maximum dimension (acrossthe opening) of less than about 200 microns (μm), more preferably,between about 50 and about 150 μm. Preferred delivery openings aregenerally circular, but one of ordinary skill in the art may modify thisto achieve specifically desired aerosol properties. The number ofdelivery openings is selected to deliver a desired misting flow. Nozzleswith one delivery opening have been shown to produce a useful aerosolplume, and other nozzles with 6 and 7 openings have also produced usefulaerosol plumes. Therefore, one of ordinary skill in the art may selectfrom one to more than ten delivery openings.

The distal end 208 of the elongate horn 204 may have surface features212 disposed thereon to substantially prevent the formation of a mistfrom any liquid that may migrate away from the nozzle 306 and to thedistal end 208 of the elongate horn 204. As shown in FIG. 5, thesesurface features 212 have an acute angle with respect to the axis of thehorn to prevent any sonic motions from driving undesired liquids intothe plume of liquids dispensed from the nozzle 306.

In an alternative embodiment shown schematically in FIG. 6, a reservoir302′ feeds a nozzle 306′ having an opening 310′, e.g., via gravity,through a conduit 304′. Similar to the embodiment of FIGS. 1-5, thenozzle 306′ fits into a receptacle 210′ formed in the distal end 208′ ofan elongate horn 204′ of a sonic generator (not shown). Activating thesonic generator energizes the liquid in the nozzle 306′ to drive itthrough the delivery opening 310′ to generate an aerosol plume. In thisembodiment, it is preferred that the height of the liquid column doesnot introduce significant flow variation during use and/or acrossmultiple uses.

In an alternative embodiment shown schematically in FIG. 7, a reservoir1000 feeds a nozzle 1002 having a plurality of delivery openings 1004,e.g., via gravity, through conduit 1006. Elongate horn 1008 of sonicgenerator 1010 fits into receptacle 1012 proximate the base 1014 ofreservoir 1000 to enable distal end 1016 of elongate horn 1008 tocontact a rear wall 1018 of the nozzle 1002 (opposite the deliveryopenings 1004). Activating the sonic generator 1010 energizes the liquidin the nozzle 1002 to drive it through the delivery openings 1004 togenerate an aerosol plume.

In another alternative embodiment shown schematically in FIG. 8, areservoir 1000′ feeds a nozzle in the form of a cap 1002′ (dimensionedto engage the distal end of the elongate horn 1008 of the sonicgenerator 1010) via gravity, through conduit 1006′. Again, the enabledistal end 1016 of elongate horn 1008 contacts a rear wall 1018′ of thecap 1002′. Activating the sonic generator 1010 energizes the liquid inthe nozzle 1002′ to drive it through the delivery openings 1004′ togenerate an aerosol plume 1020.

One of ordinary skill in the art will recognize the general assembly ofthe handheld sonic misting device of the present invention. However, theinteraction of the following elements is important to consider. Firstthe distal end of the horn and the nozzle should fit tightly to minimizeenergy loss due to inefficient motion transfer from the horn to the wallof the nozzle opposite the delivery openings to minimize heat buildupand to maximize control of the resulting aerosol plume. As the elongatehorn is generally metallic, preferably aluminum and/or titanium, thenozzle should be made out of rigid plastic. For example in theembodiment of FIGS. 1-5, the nozzle can be formed of metal orengineering plastic and machined or molded within appropriate tolerancesto fit into the receptacle at the distal end of the elongate horn. Anon-limiting list of useful materials include acetal resins (such asavailable from DuPont® Engineering Polymers under the DELRIN® brand),polyether ether ketones, amorphous thermoplastic polyetherimide (PEI)resins (such as available from SABIC under the ULTEM® brand). Inaddition, in the embodiments of FIGS. 6-8, the nozzle may be formedintegrally with the reservoir and of the same materials. Alternatively,the nozzle may be formed from one of the foregoing materials andcombined with a reservoir and/or conduit that are formed of lessexpensive and/or more easily handled materials.

The housing may be fabricated by plastic injection molding, or any othersuitable technique, and it is preferably ergonomic and adapted to fitcomfortably in a hand of a user. In a preferred embodiment, the housinghas a maximum linear dimension (length) of up to about 20 cm, morepreferably, up to about 15 cm, and most preferably up to about 10 cm.Preferably, the maximum dimension perpendicular to the length is 8 cm,more preferably, 5 cm.

The conduit between the reservoir and nozzle is preferably sufficientlyflexible for ease of manufacture. It is, however, preferred that thediameter of the conduit does not change with the application of pressureto the reservoir to dispense liquid therefrom. This permits control ofthe volume of liquid dispensed in an application of the aerosol plume.

In a preferred embodiment, the liquid section is removable from theelectromechanical section in a manner in which the nozzle is coupleableto the distal end of the elongate horn. For example, the liquid section(e.g., of FIG. 3, or any of FIGS. 6-8) may be slidably engageable withthe electromechanical section with the nozzle of FIGS. 4A-4C or the likeoriented to slide into the receptacle of the horn. Alternately, the cap1002′, of the embodiment of FIG. 8 may snap fit over the distal end ofthe horn.

The present invention is useful in the delivery of aerosol plumes ofmedication and/or moisturizing solutions in a more sanitary manner thancurrently provided. Sonic generation of aerosol plumes can provide veryfine mists, having a droplet size between about 20 and about 60 μm,given by the practical range of frequencies for the ultrasonic hornbetween 20 kHz and 200 kHz. As indicated above, as sonic generators aremore expensive than traditional squeeze and spray bottles, it isimportant to separate the expensive and reusable sonic generator andhorns from the relatively inexpensive and potentially disposable liquidreservoirs. Therefore, in use, a replaceable liquid section 508, such asshown in FIG. 3, can be slidably inserted into the electromechanicalsection 506. As a result of this, the distal end 208 of the elongatehorn 204 is engaged with the nozzle 306. Any protective covering (e.g.,cover 504) can be removed from the nozzle, 306, and the misting device100 can be energized.

To create an aerosol plume, the activation switch 408 is depressed, andthe linear motor 310 drives the piston 312 to deliver a controlled forceon the lower surface of the reservoir 314. This action forces liquidthrough conduit 304 to nozzle 306 and delivery opening(s) 308. Thissequence may be repeated until the reservoir is emptied. The now-emptyliquid section 508 can be removed and a new liquid section 508,including a new nozzle 306, is inserted. The new nozzle is notcontaminated as a result of the previous use of the misting device.

The specification and embodiments above are presented to aid in thecomplete and non-limiting understanding of the invention disclosedherein. Since many variations and embodiments of the invention can bemade without departing from its spirit and scope, the invention residesin the claims hereinafter appended.

What is claimed is:
 1. A handheld misting device comprising a housinghaving a dispensing window, the housing comprising: a) anelectromechanical section comprising: i) a sonic generator comprising aconverter and an elongate horn having a proximal end coupled to theconverter and a distal end having a receptacle formed therein; and ii) apower source coupled to the sonic generator; and b) a liquid sectionarranged and configured to be securely attachable to theelectromechanical section and to contain: i) at least one reservoircontaining a liquid; and ii) a conduit extending from the at least onereservoir to a nozzle removably inserted into the receptacle formed inthe distal end of the horn to deliver the liquid through a deliveryopening formed in the nozzle, whereby activating the sonic generatorenergizes the liquid in the nozzle to generate an aerosol plume that isdelivered through the dispensing window.
 2. The handheld misting deviceof claim 1 wherein the liquid section is disposable.
 3. The handheldmisting device of claim 1 wherein the at least one reservoir containingthe liquid comprises a collapsible reservoir coupled to a linear motorto control delivery of the liquid through the conduit to the nozzle. 4.The handheld misting device of claim 1 wherein the nozzle is arrangedand configured for removable placement over the distal end of theelongate horn.
 5. The handheld misting device of claim 1 wherein theliquid section is arranged and configured for slidable engagement withthe electromechanical section.